Hat strap



FIG. 1 is a front elevational view of the hat strap showing my new design;

FIG. 2 is a right side elevational view thereof;

FIG. 3 is a rear elevational view thereof;

FIG. 4 is an enlarged end elevational view thereof; and,

FIG. 5 is an enlarged opposite end elevational view thereof. 

The ornamental design for hat strap, as shown and described. 